The present invention relates to a method of producing a medical report based on a volumetric scan of one or more internal organs of a subject, said method comprising the steps of a) calculating two-dimensional images for simulating a three-dimensional view of the one or more internal organs based on the volumetric scan; b) storing one or more of the two-dimensional images; and c) incorporating one or more of the stored two-dimensional images in the medical report.
Such a method is known from the article “FreeFlight: A Virtual Endoscopy System” by Vining et al., CVRMed MRC AS 1997 First Joint Conf. Computer Vision Virtual Reality, pages 413-416.
The known method concerns a virtual medical examination technique of a human patient. Based on a volumetric scan of said patient, for instance generated by means of Computed Tomography, and by means of virtual reality techniques a medically skilled person can examine the internal organs of the patient without the need for invasive examination. The three-dimensional view is usually displayed on a powerful computer, such as a workstation. A first medically skilled person can evaluate the three-dimensional view for different purposes, such as diagnosis, preparing interventional procedures and rehearsing surgical operations. In case of a diagnosis the textual part of the diagnosis is incorporated in a medical report for review on a low-end computer by a second medically skilled person. To visualize the diagnosis the text is usually accompanied by static screenshots of areas of interest to which the diagnosis refers.
The known method has the disadvantage that the second medically skilled person reviewing the medical report, which is usually an interventional physician, receives only limited information with a static character and misses the full viewing interaction that was available to the first medically skilled person making the diagnosis.
It is an object of the method according to the invention to produce a medical report with more information which is still suitable for review on a low-end computer.
The method according to the invention is therefore characterized in that the method further comprises the steps of:
d) Providing a dynamical display of the stored two-dimensional images for simulating at least part of the three-dimensional view; and
e) Incorporating the dynamical display of the two-dimensional images in the medical report.
Advantageously the large computations involving the calculation of the two-dimensional images can be performed on a suitable high power computer first and the resulting medical report incorporating the stored two-dimensional images can then be transferred to a low-end computer for review. By dynamically displaying the stored two-dimensional images the reviewer keeps the possibility to look around in at least part of the simulated three-dimensional view thus receiving important extra information.
It is noted that method steps a) through d) are known per se from the article “Mastering Interactive Virtual Bronchioscopy on a Low-End pc” by Wegenkittl et al in Proc. IEEE Visualization Conf. 2000, pages 461-464, ACM Press, 2000. This method, however, refers only to the medical examination of the trachea of a patient based on a volumetric scan thereof and is not used for producing a medical report.
According to a first preferred embodiment of the method according to the invention step d) further comprises the step of displaying the stored two-dimensional images in a sequence. This way the reviewer is given the impression to be immersed in the three-dimensional environment as if he or she could “fly through it”.
According to a second preferred embodiment of the method according to the invention step d) further comprises the steps of calculating a virtual environment based on the stored two-dimensional images at one or more viewpoints in the three-dimensional view; and allowing interactive inspection of the virtual environment. This embodiment provides the user the possibility to dynamically inspect the environment of a viewpoint interactively.
In a further preferred embodiment of the method according to the invention step b) for one or more viewpoints further comprises the steps of: projecting a number of two-dimensional images visible in different directions from a view point of the three-dimensional view onto the corresponding sides of an object; unfolding the object in two dimensions; and storing the two-dimensional unfolded object image. The thus calculated and stored images are suitable for processing by a low-end computer. Preferably the object is a cube. This allows for an intuitive view of the patient data in two dimensions.
In yet a further preferred embodiment the method further comprises the step of folding up the object image, thus forming the virtual environment. The already available information is now efficiently used to recreate the virtual environment for each viewpoint marked as important by the first medically skilled person producing the medical report.
According to another preferred embodiment of the method according to the invention slips with additional image information are added to the borders of a number of the sides of the object. Preferably the slips comprise duplicate image information. This embodiment assures that practically all information is visible and no vital information is inadvertently lost by defining the borders or edges of the object onto which the two-dimensional images are projected or mapped. This is especially an advantage when the internal organ under examination has an irregular surface, as is e.g. the case with the colon wall. Vital information about polyps or cancer could be hidden in the convolutions thereof. By using this embodiment the complete information becomes visible to a very high degree of nearly 100%.
In yet another preferred embodiment the method further comprises the steps of:
f) editing and/or analyzing a number of the images; and g) adding the edited and/or analyzed images to the medical report. The step of editing may comprise all sorts of processing of the subject data performed by a skilled person, such as defining a cross section through one or more of the internal organs of the subject. The step of analyzing may comprise all sorts of processing of the subject data performed by a skilled person, such as measuring at least part of the internal organs. This advanced embodiment offers the important possibility of extending the medical report with additional information based on the expertise and knowledge of the first medically skilled person.
The invention further refers to a system to carry out the method according to the invention, comprising a data acquisition device comprising means for recording the volumetric scan, which data acquisition system is connected to at least one high-end computer with high computational power, which high-end computer comprises means for producing the medical report and is connected to at least one low-end computer, which low-end computer comprises means for displaying the medical report.
The invention also concerns a computer program to carry out the method according to the invention.